/****公共样式****/
html,body{
    width:100%;
}
*{
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
}
a{
    text-decoration: none;
}
li{
    list-style: none;
}
.span1, .span2, .span3, .span4, .span5, .span6, .span7, .span8, .span9, .span10, .span11, .span12, .span13, .span14, .span15, .span16, .span17, .span18, .span19, .span20 {
    float: left;
    margin-left: 14px;
    min-height: 1px;
} 
/*清除浮动产生影响的样式*/
.clearFloat:after{
    content: '';
    height: 0;
    display: block;
    visibility: hidden;
    clear: both;
}
.clearFloat{
    zoom: 1;
}